Oceane lived her entire life with her mermaid pod, The Moontails. But when she goes up to take a first and last glance of the human world, she meets and boy, about 13 years old, like her. Then, back underwater, Oceane can't stop thinking about him. She soon forgets though, and grows up. On her 16th birthday, she goes with her mother to collect clams. She strays from her mother's path, and sees a surfer who had a shark going towards him! Oceane saves the surfer and leaves, but not after he sees her and her tail! Later nights lead to memories of the boy.